In which of the following physical or chemical transformations is the overall change in entropy ($\D

Question

In which of the following physical or chemical transformations is the overall change in entropy ($\Delta S$) negative?

Professor PC Thomas Classes · Answer

(d) : Entropy serves as a direct quantitative measure of a system's microscopic disorder or randomness. Boiling (liquid $	o$ gas), dissolution (solid $	o$ aqueous ions), and isothermal expansion (increasing available volume) all fundamentally increase the available microstates and spatial freedom of the constituent particles, leading to $\Delta S > 0$. Conversely, the isothermal compression of a gas forces the molecules into a much smaller volume, heavily restricting their spatial positions and reducing randomness, ensuring $\Delta S < 0$.